Abstract: Take Lin2-ping5 well as an example, which was injected cement to plug interval, this article has compared the selections for the technology of plugging horizontal interval in mechanical sand controlling horizontal wells, and analyzed main factors which influence plugging by injecting cement plug in horizontal interval.Actual measures have been proposed for improving plug effect through injecting cement plug in horizontal interval, the measures are enhancing suspension stability of cement slurry to prevent intensity of cement plug decreasing caused by difference between gravity of cement slurry, adding anti-expansion agent to reduce shrinkage of cement, taking thickener as pad fluid and displacement fluid to resolve cement slurry running horizontally problem which caused by serious difference of density and viscosity between cement slurry and displacement fluid.The application on site shows it is effective only through one time, that would be referenced by other Oilfields for selecting and using plugging technology of horizontal well.